Specifically hwy 287 / hwy 20. I'm driving out to IF next week to see my girlfriend and I'm trying to decide which way I want to go. Obviously the weather will have a big effect on my decision and if it's anything like SD, it will change every half hour the whole way there. I would rather not go all the way to I-15 if I can help it since that adds an extra hour or more to an already 10+ hour drive, but I'll be in my car so I should stay on decent roads. So far her opinion of the snow plowing abilities of the Idaho DOT is not that great, so she thinksI-90 to Butte and then I-15 might be my best bet during the winter. Has anyone been between Bozeman and Idaho Falls lately? I'm assuming there is quite a bit of traffic in the west yellowstone and island park areas during the snowmobile season, but they're in 4WD trucks too usually so the road conditions might not be good enough for a car still.